Self-heating container having hermetic sealing means



Oct. 14, 1952 J RIVQCHE 2,613,664

SELF-HEATING CONTAINER HAVING HERMETIC SEALING MEANS Filed Nov. 5, 1950 INVENTOR. v EU GENE J. Rxvo can jg 2. BY f FSTTOIRINEYS Patented Oct. 14, 1952 SELF-HEATING CONTAINER HAVING HERMETIC SEALING MEANS Eugene J. Rivoche, Washington, D. C.

Application November 3, 1950, Serial No. 193,866

8 Claims.

This invention relates to self-heating containers for packaged food or other material of the type which contains, in a compartment separate from but adjacent the packaged-material compartment, burnt lime or other exothermic material which on reaction with water will liberate sufiicient heat to raise the temperature of the packaged material to a predetermined extent. Such containers are well adapted for use under conditions where the usual means for preparing hot foods are not available.

In manufacturing such containers, the amount of burnt lime, mixtures containing the same, or other exothermic material, which is used is just suflicient when activated with water to raise the temperature of the food or the like to a predetermined degree. Consequently, the exothermic material should be hermetically sealed to prevent absorption of moisture from the atmosphere and such resultant deterioration of the exothermic material as would prevent it from liberating the desired amount of heat. To that end, the invention contemplates a self-heating container of simple construction and ease of manufacture and assembly in which the compartment for the exothermic material is effectively and hermetically sealed.

If the self-heating container is one which carries an adequate amount of water to activate the exothermic material, the sealing means will effectively seal the compartment for the exothermic material both from such Water and from the atmosphere; while if the self-heating container is one to which water from an extraneous source must be added, it is only necessary that the sealing means hermetically seal such compartment from the atmosphere.

The use of burnt lime as the exothermic material is preferred as it is cheap, liberates a large amount of heat, is readily available, and is easy to handle in manufacturing self-heating containers. However, burnt lime, von reaction with water, expands to several times its normal volume. Hence, when burnt lime is utilized as the heating material it is necessary that some means be provided to permit at least partial expansion of the lime, or else the container must be constructed of material stronger than that normally used in tins for the canning of food. Leaving sufficient free space in the lime compartment to permit sufficient expansion of the lime so that the use of stronger stock for the container is not necessary is undesirable as it adds to the overall size of the self-heating container, a disadvantage from the standpoint of transportation.

In accordance with the present invention, the food container is mounted for telescopic move-- ment in an outer container and the hermetic sealing means is formed between cooperating portions of the food container and the outer container, and is effective to maintain the de-- sired hermetic seal until the self-heating container is to be put into operation, if the container carries the activating water, or if it doesnt carry the water, until the expansion of the lime builds up a predetermined pressure, when it automatically is broken to permit telescopic movement of the food container.

The invention will be further described in connection with the accompanying drawing, but it is to be understood that such further description that type in which water from an extraneous source is used to activate the exothermic material.

In the drawings, the container 1 for food.

soup, or any other material which it may be desired to heat without the use of heat from extraneous source, which material hereinafter will be referred to as food, preferably is formed of the usual tinned or lacquered metal stock commonly used in the canning industry.

The food container 1 is nested in an outer container 2 for limited telescopic movement, as hereinafter described. The outer container consists of a bottom 3 and a side wall 4, but no top. The side wall 4 terminates short of the upper end of the food container a distance sufiicient to enable one to get a good grip on the protruding end of the food container. The upper edge portion of the side wall 4 lies against and is sealed to the side wall of the food container. Such sealing preferably is obtained by a sealing strip of rubber, plastic, or other adhesive material 5 which readily may be removed when the container is to be put into operation.

The side wall 4 is circumferentially grooved or otherwise distorted to provide inwardly-protruding, vertically-spaced extensions 6, l and 8.

The extension 6 has a substantially flat hori zontal upper surface 9 which forms a seat for a sealing ring or gasket l I of rubber or other resilient sealing material, against which the lower portion of a cooperating sealing flange l2 of the food container is maintained in hermetic sealing engagement.

The grooving to form the extension I is less abrupt and less deep to form a gradually inwardly-tapering portion [3 which partially overlies the sealing flange I2 and normally holds the flange [2 in tight sealing engagement with the sealing ring H.

The upper extension 8 also is less deep than the extension I and has a substantially horizontal under surface M, which on telescopic movement of the food container l outwardly of the outer container 2 is engaged by the flange l2 and limits outward movement of the food container.

The space between the bottom of the food container and the bottom of the outer container forms a compartment of such size as to receive an amount of lime or other exothermic material !6 just sufiicient, when activated, to heat the food in the food container to the desired temperature.

In this form of the invention, water H for activating the'lime is stored in the space between the side walls of the food container and the outer container. 7

When it is desired to place the selfheating container in operation, it is only necessary to remove the sealing strip '5 and to grip the upper end of the food container and pull it upwardly until the flange I2 is pulled past the extension 7; the gradual taper of the portion 13 and the inherent resiliency of the thin metal stock from which the side wall of the outer container is formed make this operation relatively easy.

Once the flange 52 has been pulled above the extension 7, the water will flow into th lime compartment and activate it with the liberation of heat sufficient to raise the temperature of the food in the container 1 to a desired eating temperature.

The expanding lime will lift the food container until the flange l2 strikes the limiting surface 14 when outward movement of the food container in the outer container will be arrested, as indicated in dotted lines in Fig. 1. The pressure exerted by the lime will cause a pressure contact between the flange l2 and the surface [4 which will prevent any of the lime being forced past the extension 8.

The gradual downward taper of the upper surfaces l8 and IQ of the extensions 8 and 7, respectively, enable the food container to be forced inwardly past the extensions 8 and l during assembly, to cause the flange l2 to be brought into tight sealing contact with the sealing ring ll.

The form of the invention illustrated in Fig. 2 is the same as that illustrated in Fig. 1, except that the water is not stored in the space between the side walls of the food container and the outer container and must be added from an extraneous source.

To facilitate the use of an amount Of water sufficient to give maximum liberation of heat by the exothermic material, the bottom 3 of the outer container 2' is dished to provide a space, when the container is inverted, of just the right size to hold an amount of water to most effectively activate the exothermic material.

The dished bottom 3 is formed with slight indentations 2| into which the pointed end of a puncturin tool may be placed to facilitate the puncturing of the bottom wall to form holes therethrough through Which water may pass to be absorbed by and react with the exothermic material.

In all other respects the self-heating container of this form of the invention is the same as that of Fig. 1, and like parts are designated with the same reference characters, primed.

When the self-heating container of this form of the invention is to be put into operation, it is inverted, the dished bottom 3 punctured with a suitable tool and filled with water. As soon as the water has passed through the holes and is absorbed by the lime the container is turned right side up again and left until the heat liberated by the lime has heated the food to a sufficient temperature for eating.

In either form of the invention, the food container may be opened before it has been heated to a temperature such as will make its handling diflicult, or it may be left sealed until the food is heated to the eating temperature. If opened at the beginning of the heating operation, access can be had to the food for stirring during the heating thereof.

I claim:

1. A self-heating container comprising an inner container for food, anouter container having a bottom and a side wall in which said food container is mounted, the side wall of the outer container having an inwardly-extending peripheral extension, the inner container being supported by said extension, a water-tight seal between the inner container and said extension, and material which on reaction with water liberates heat between the bottom of the food container and the bottom of the outer container.

2. A self-heating container as defined in claim 1 in which the extension has a generally horizontal upper surface, and the water-tight seal comprises a gasket between said surface and the bottom of the food container.

3. A self-heating container as defined in claim 1 in which the water-tight seal isa sealing gasket and in which means are provided for forcibly holding the food container against, the sealing asket.

4. A self-heating container as defined in claim 1 in which the water-tight seal is a sealing gasket and in which releasable and resilient means are provided for forcibly holding the food container against the sealing gasket.

5. A. self-heating container as defined in claim l in which a portion of the side wall of the outer container overlies a portion of the food container to releasably and forcibly hold the food container against the sealing gasket.

6. A self-heating container as defined in claim 5 in which both the food container and the side wall of the outer container have cooperating inwardly and upwardly extending portions just above the extension which cause the food container to be releasably and forcibly held against the sealing gasket.

7. A self-heating container as defined in claim 1 in which the food container is mounted for telescopic movement in the outer container and.

the upper portion of the side Wall of the outer container has an inward extension for engagement by an outward extension of the food container to limit outward telescopic movement of the food container in the outer container.

8. A self-heating container as defined in claim 1 in which water to activate the heat-liberating material is sealed in the space between the side walls of the food container and the outer con- 5 tainer, at the side of said water-tight seal remote Number from the heat-liberating material. 1,971,364 EUGENE J. RIVOCI-IE. 2,212,441 2,327,412 REFERENCES CITED 5 2,327,447 The following references are of record in the 2,367,409 file of this patent:

UNITED STATES PATENTS Number Number Name Date 10 70,425

794,848 Bohm July 18, 1905 Name Date Zimmer et a1 Aug. 28, 1934 Katz Aug. 20, 1940 Fink Aug. 24, 1943 OBrien Aug. 24, 1943 Kuhler Jan. 16, 1945 FOREIGN PATENTS Country Date Australia Nov. 10, 1915 

